Performance Technic BMW 135i - M3 V8 Swap

The 2011 BMW 1M—or 1 Series M Coupe, to use its official title—rapidly earned iconic status, and deservedly so. First of all, it's incredibly rare, with only 1,000 cars available in the U.S. Secondly, it was equipped with the BMW M3 chassis to give it superb handling, while having the benefit of the lighter, torquey 3.0L turbo motor. And thirdly, it looked badass with its widebody styling.

Of course, there were those who felt BMW should have gone the whole hog and used the 4.0L M3 V8 engine as well, but that would have overshadowed the M3 itself and required more extensive development, pushing up the cost.

With that said, it was inevitable the aftermarket would execute the swap, and German BMW specialist G-Power duly obliged with the G1 V8 Hurricane RS. We featured it in the 3/14 issue of European Car magazine, and can be found at europeancarweb.com.

Boasting 600 hp, thanks to an ASA supercharger, and finished in chocolate brown, it was magnificent but thousands of miles removed. What we wanted was something similar on U.S. soil. And if it was evading the Highway Patrol while running moonshine, so much the better!

Sadly, such a scenario wasn't realized, but we were still delighted to see, hear, and touch a similar conversion at this year's Bimmerfest West show in Pasadena, California.

It was housed in the Toyo Tires booth, and we initially paid it little attention since it looked like a 1M with aftermarket wheels. It was only after poking around it for a few moments that the full extent of its modifications became apparent.

We quickly tracked down the owner, Marco Svizzero from San Francisco, California, as well as the tuner, Joey Gaffey from Performance Technic in Dublin, California. The pair was slightly overwhelmed by the response the car received from Bimmerfest visitors and confessed it was barely finished in time for the show.

1M conversion

Creating a project such as this is always a confluence of circumstances and happenstance. For Marco, he was lucky to find a company willing and able to install the M3 V8 into his 2008 BMW 135i, while Joey was lucky to be in the right place, at the right time when Marco was ready to pull the trigger.

When speaking to Joey, it was apparent he had been building up to this car over the past five years. It all began when he walked away from his job as a marketing executive at his father's software firm in order to follow his passion. As a lifelong BMW enthusiast, he established his new business to work on Munich's finest.

Where happenstance intervened was that Joey didn't want to simply install suspension and exhaust systems. "I wanted to create a company capable of doing custom swaps. It's not something many shops are prepared to do, but it's what I really love," he told us.

His first major project was a manual transmission conversion on a BMW 540i M Sport Touring. The car had a number of M5 exterior pieces and attracted a lot of local and Internet attention, helping the company grow rapidly.

Performance Technic would make a name for itself by carrying out 6MT conversions to E46 M3 SMG cars. In fact, the company created a kit of parts to allow customers to make it a DIY conversion.

The custom creations were building steam and would culminate in Performance Technic's biggest achievement to date: Marco's 135i. "It's undoubtedly our most significant undertaking," Joey confirmed.

If we backtrack slightly, Marco had been a Performance Technic (PTech) customer for a year or so, having several of his early modifications fitted on-site and taking part in several of the shop's track days.

At this point, the coupe already wore its shiny new suit: Marco had decided to give his 135i more muscle and ordered the genuine 1M body kit, fitting the front end himself, with its distinctive front bumper and wider front fenders.

At the rear, he had DTM Autohaus in El Monte, California, fit the wider rear fenders since these necessitated cutting away the original metalwork and grafting on the new fender flares. They also added the 1M rear bumper and side skirts to complete the transformation.

With the car painted in BMW's Alpine White 3, Marco approached composite specialists Revozport and partnered with them to complete the exterior. Based in Hong Kong, the company's 1M Raze package is regarded by Marco as "The most complete aftermarket aero kit for the car and some of the best carbon fiber I've ever seen."

The Revozport BMW 1M Raze components comprised the large front splitter (with APR supports) as well as the lightweight hood and trunk, trunk lip, rear diffuser, and GTS rear wing.

Once fitted by Marco, the hood and trunk were painted by DTM, but the owner opted to leave the Revozport carbon-fiber roof in its natural weave. As it happens, it has a 1x1 glossy weave, mimicking the factory E92 BMW M3 roof. The rest of the parts were made in 2x2 satin weave to Marco's specification.

To further reinforce the little coupe's track prowess, it had been fitted with a rollbar built by TC Designs. "I had them make a 'cage similar to the M3 GTS as a nod to my OEM+ theme," Marco explained. He would also install carbon/kevlar Recaro Profi SPA seats for the same purpose.

Engine Swap

Moving forward in time again, the 135i was experiencing turbo problems after several track days, so Marco was discussing turbo upgrades when Joey dropped the bomb: "I suggested we install the S65 M3 4.0L V8 engine. I'd never done it before but figured it had to be possible," Joey explained. "I was sure BMW must have fitted one into the 1M when they were developing the car. They had to wonder what it would be like," he continued. "It would have undoubtedly outshone the M3, so it never made it into production, but I wanted to give it a try."

The team didn't rush at the task at hand. They worked methodically to acquire the vast number of parts needed to complete the task. It started by sourcing a salvaged M3 in England, a solution that made the best economic sense. They lucked out by finding a 2009 M3 that had only covered 27,000 miles before meeting its untimely end. So the PTech crew made a list of the parts they would require, which were dismantled from the car and shipped over.

"The toughest task was actually the wiring," Joey explained. "We had to get the M3 wiring harness and hook up the engine, DME, CAS (key transponder), and ensure all its functions were operational, including things like the ABS, traction control, MDM, stability control, etc. Then it had to be spliced into the 135i harness to make everything work."

Since they didn't know the condition of the donor engine, it was stripped and fitted with WPC rod bearings and ARP hardware to avoid any problems from the S65's Achilles' heel.

When reassembling, PTech added a baffled oil pan to avoid oil starvation on the track, as well as Turner Motorsport pulleys and an iND intake plenum. The exhaust would be a combination of M3 headers and cats with a 1M rear section and muffler. It was assembled in such a way that the cat-back system can be easily replaced at a later date if Marco feels the need. Interestingly, the guys chose to retain the stock emissions equipment to ensure the car would pass California smog regulations since the owner will be driving it to shows, track days, and work on a regular basis.

The engine block was fitted from underneath the car in order to clear the headers. It would sit on solid M3 engine mounts that were bolted to the M3 front subframe. Clearance was very tight, but once a custom oil cooler bracket and oil lines were fitted, the installation looked like stock. And it's just as well it wasn't a difficult operation because the team would fit and remove the V8 a total of six times to fit the exhaust, check the wiring, etc.

Once the wiring was complete, the engine started and ran on the M3 DME, but it triggered several check engine lights. So BPM Sport from Los Angeles was enlisted to work on the coding so the DME could recognize items such as the oil level and brake sensors. They also coded the airbags, gauges, and EDC delete before flashing the ECU with its Race software, designed for a car with full exhaust mods, which may soon follow...

Chassis & Trans

Retaining the M3's six-speed manual transmission, Performance Technic had a custom driveshaft built to fit the shorter body. It was attached to the M3's differential that sat in the M3 rear subframe, which was solidly mounted to the 135i bodyshell. A series of solid rear bushings and Heim joints were used to ensure the car would be competitive on the track and allow camber, castor, and toe adjustment.

With the subframes fitted front and rear, PTech proceeded to install the M3's knuckles, wheel bearings, and brake assemblies. The brakes would be upgraded to StopTech's Trophy kit, boasting six-piston calipers up front with 380mm grooved rotors, while four-piston calipers and 355mm rotors live in the rear.

Again, these were part of PTech's track preparations, ensuring the car could be fully exploited in its natural environment. As such, it also received PSi/Öhlins Raceline coilovers as well as Racing Dynamics sway bars, monoball kits for the front control arms, and Bimmerworld rear wishbones.

We don't want you to think this car is either about show or straight-line performance. The tuner and owner have been very deliberate in preparing the car for any situation, and we're confident it will excel at whatever it does.

With the M3 subframes and suspension components installed, the wheel offsets were altered to avoid rubbing issues. As a result, the car has rather unique 18x9.5-inch front and 18x10-inch rear HRE R43 wheels, both with a 25mm offset. These were wrapped in track-ready Toyo R888 R-compound tires for the reasons stated above.

We learned Marco intends to swap the rear wheels to the front and go wider on the back to put more rubber on the road, but for now the HREs are allowing him to put some valuable miles on the rebuilt engine. Before it heads onto the track, Marco and Joey have a series of car shows scheduled, allowing them to show off their work and maybe attract new clientele. As such, they made some concessions to comfort and style, including some very nice Revozport carbon-fiber door cards with alcantara trim panels to match the OEM BMW 1M anthracite headliner.

Insisting on only fitting the best products, Marco specified the steering wheel, shifter, e-brake boot and lever, as well as full carbon-fiber trim from BMW Performance. He also added a P3 Cars vent-mounted gauge and used an Alumalite rear seat-delete panel to hide the bare floor once the rollbar was fitted.

You can read our driving impressions in the separate sidebar, but we did ask Marco to summarize his experience: "The guys at PTech had already exceeded my expectations with their previous work on my car, so once we decided to do the swap, I had full confidence they could tackle the task and produce a solid, factory-quality car with working electronics," he said. "The finished car is a masterpiece in my eyes and couldn't be more perfect."

Joey was also very pleased with the outcome: "It's a great car; very rigid but not harsh. It feels track-bred and is a good-looking car."

So what would it cost to replicate something similar? Joey estimated his company would charge $80,000 to $100,000 to conduct the engine swap, depending on final specification. He also quoted a construction time of two to three months but pointed out Marco's car had a great deal of work beyond the engine swap.

It's also worth pointing out the 135i doesn't have much room for wide tires under its stock fenders, so fitting the 1M body kit would also be a wise investment to ensure you get the power to the ground. So if you've got six figures burning a hole in your pocket, and you're looking for an awesome track car, we might suggest you visit Performance Technic and discuss your options.

Driving Impressions

The CHP cruiser ahead wasn't what we wanted to see, but its presence gave us time to warm the V8 as we climbed Angeles Crest Highway's slithery switchbacks. The Meisterschaft exhaust echoed off the canyon walls as the Toyo R888s got steadily stickier.

After the road cleared, it was time to let loose. Well, not completely because the engine wasn't fully broken in. There was a 5,000-rpm curfew imposed, which is where the M3's S65 V8 starts doing its best work, but we short-shifted and tried to rely on both the midrange torque and a heavy dose of restraint.

That meant our time behind the wheel was more about the handling, where this car excelled. I thought it might be nose-heavy, yet the M3 drivetrain, which is slightly heavier than the 135i's, didn't adversely affect weight distribution. This is because the balance is still good thanks to the addition of the rear differential.

Corner balanced, riding on M3-spec Öhlins coilovers, and using Dinan monoball front control arms, the turn-in was race-car quick. Where most cars need a moment to lean on the tires and compress the springs and bushings before taking a set, Svizzero's 1M V8 immediately starts hunting for the apex. The Toyo R888s hang on tenaciously, with the fronts eventually letting go slowly and predictably.

The combination of turn-in precision, grip, and predictability gives you the confidence to dive into corners faster than you might normally, making this machine one of the sharpest canyon carvers I've ever driven.

Even though we were limited to 5,000 rpm, the modified S65 had plenty of midrange tug out of the corners. Being nearly 400 pounds lighter than an M3 coupe was a significant factor.

Braking and downshifting before the turns was as equally satisfying. The Rogue Engineering short shifter felt deliciously direct and perfectly weighted, while a light touch on the StopTech Trophy anchors wiped off loads of speed.